JP6115779B2 - Switching board - Google Patents

Description

  The present invention relates to a switching substrate.

  In recent years, automobiles equipped with an auxiliary power source in addition to a main battery have been developed in order to improve fuel economy and consider the environment. For example, regenerative energy at the time of braking is stored in an auxiliary power source and used for power supply to electrical components during traveling, thereby reducing the amount of power generated by the alternator and improving fuel efficiency. Further, when the engine is restarted after the idling stop, power is supplied to the starter from the auxiliary power source, so that it is possible to prevent electrical components from being momentarily interrupted or the main battery from being deteriorated due to a momentary drop in the voltage of the main battery.

  A switching board having a function of switching the power supply form may be installed between the main battery and the auxiliary power source in accordance with the operation state of the vehicle such as traveling or idling stop.

  As a switching substrate, a substrate having a mechanical relay corresponding to a large current has been conventionally used, but replacement of the mechanical relay with a semiconductor switching element has been proposed for the purpose of miniaturization, long life, and noise reduction. . As the semiconductor switching element, it is assumed that a power semiconductor such as a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) is used (see Patent Document 1).

JP 2009-146933 A

  By the way, in general, in a switch using a MOSFET, a parasitic diode with a pn junction is generated between a source and a drain. Therefore, even if the gate is turned off, a current flows from the source side to the drain side through this parasitic diode, so that the current flow from the source side to the drain side cannot be completely blocked. Therefore, in order to be able to cut off the bidirectional current, two MOSFETs may be connected in series so that the directions of the parasitic diodes are opposite.

  However, when trying to design such a complicated circuit, the structure of the switching substrate tends to be complicated.

  The present invention has been completed based on the above situation, and provides a switching board having a simple configuration arranged between a main power supply and an auxiliary power supply in a vehicle including a main power supply and an auxiliary power supply. The purpose is to do.

  The present invention relates to a vehicle including a main power source and an auxiliary power source, a switching board disposed between the main power source and the auxiliary power source, and an insulating plate made of an insulating material, on one surface of the insulating plate. A control circuit board comprising: a conductor circuit disposed; a plurality of mounting windows penetrating from a surface of the insulating plate on which the conductor circuit is provided to a surface on the opposite side; and a surface on the opposite side of the insulating plate. An input bus bar and an output bus bar that are spaced apart from each other, and a plurality of semiconductor switching elements that are mounted on the circuit structure and include a drain terminal, a source terminal, and a gate terminal, The conductor circuit includes a control circuit and a connection circuit disposed between the input bus bar and the output bus bar, and some of the plurality of mounting windows are provided inside the input bus. A first mounting window in which a part of the output bus bar is exposed; the other mounting window is a second mounting window in which a part of the output bus bar is exposed; The switching element is disposed inside the first mounting window, the drain terminal is connected to a part of the input bus bar, the source terminal is connected to the connection circuit, and the gate terminal is connected to the control circuit. The other semiconductor switching element is disposed inside the second mounting window, the drain terminal is connected to a part of the output bus bar, and the source terminal is connected to the connection circuit. The switching substrate is a second semiconductor switching element whose gate terminal is connected to the control circuit.

  According to the above configuration, a bus bar, a control circuit substrate, and a semiconductor switching element necessary for the switching substrate disposed between the main power supply and the auxiliary power supply can be simply laid out, and a simple configuration switching substrate is provided. it can.

  As embodiments of the present invention, the following embodiments are preferable.

  The input bus bar is disposed at an edge on the output bus bar side between a plurality of first convex portions projecting toward the output bus bar and two adjacent first convex portions, and the output bus bar is A first recess recessed on the opposite side, and the output bus bar has, on the input bus bar side edge, a plurality of second protrusions protruding toward the input bus bar, and two adjacent second protrusions And a second recess recessed on the opposite side of the input bus bar.

  According to the above aspect, it is possible to avoid the control circuit board from being broken along the gap between the input bus bar and the output bus bar when an unexpected large force is applied to the switching board.

  ADVANTAGE OF THE INVENTION According to this invention, the switching apparatus of the simple structure distribute | arranged between a main power supply and an auxiliary power supply can be provided in a vehicle provided with a main power supply and an auxiliary power supply.

The perspective view of the switching device of an embodiment The exploded perspective view of the switching device of an embodiment The perspective view which looked at the switching board of an embodiment from the bus-bar side Top view of switching substrate of embodiment Enlarged view inside circle R in FIG. AA line sectional view of FIG. Enlarged view inside circle S in FIG. The figure which shows the circuit structure of the switching apparatus of embodiment. The figure which shows an example of the manufacturing method of the circuit structure of embodiment The perspective view which looked at the switching board of a modification from the bus-bar side

An embodiment of the present invention will be described with reference to FIGS.
The switching device 1 according to the present embodiment is a vehicle including a main battery 90 (corresponding to a main power source) and an auxiliary battery 91 (corresponding to an auxiliary power source), and supplies power from the main battery 90 and the auxiliary battery 91 to the electrical component 92. Is switched. As shown in FIG. 8, the main battery 90 and the auxiliary battery 91 are arranged in series and supply electric power to the electrical component 92. Switching device 1 is arranged in series with respect to main battery 90 and auxiliary battery 91 between main battery 90 and auxiliary battery 91.

  As shown in FIGS. 1 and 2, the switching device 1 includes a switching board 10 and a casing 80 that houses the switching board 10. The switching substrate 10 includes a circuit configuration body 11 and six semiconductor switching elements 60A and 60B mounted on the circuit configuration body 11. The circuit structure 11 includes a control circuit board 20, and two bus bars 30 and 40 and a separator 50 that overlap the control circuit board 20 via an adhesive layer 53.

  The control circuit board 20 is a printed board including a conductor circuit 22 made of a conductive material on one surface side of an insulating plate 21 made of a glass base material or a glass nonwoven fabric base material. A connector 23 for connecting the control circuit board 20 to an external control device (not shown) is disposed at one end of the control circuit board 20.

  As shown in FIG. 4, the control circuit board 20 has six mounting windows 24A and 24B for mounting the semiconductor switching elements 60A and 60B. The mounting windows 24A and 24B are rectangular openings penetrating from the surface on which the conductor circuit 22 is arranged on the control circuit board 20 to the opposite surface, and the size of the openings is the semiconductor switching element 60A. , 60B larger than the outer shape. Of the six mounting windows 24A, 24B, three mounting windows (first mounting windows 24A) constitute a set of first mounting window groups 25A arranged in a row. Of the six mounting windows 24A and 24B, the remaining three mounting windows (second mounting windows 24B) constitute a set of second mounting window groups 25B in a line. The two sets of mounting window groups 25A and 25B are arranged in parallel with a space between each other.

  The conductor circuit 22 includes a control circuit 22B and a connection circuit 22A. The control circuit 22B has a predetermined pattern, one end of which is arranged in the vicinity of each mounting window 24A, 24B, and the other end is connected to a terminal provided in the connector 23, although not shown in detail. . The connection circuit 22A is disposed on the control circuit board 20 in a region between the two sets of mounting window groups 25A and 25B with a space from the control circuit 22B.

  One of the two bus bars 30 and 40 is the input bus bar 30 and the other is the output bus bar 40. As shown in FIG. 3, the input bus bar 30 is a rectangular thick plate made of a conductive material (copper or copper alloy in this embodiment). The input bus bar 30 includes a bolt insertion hole 31. The bolt insertion hole 31 is a through-hole penetrating from one plate surface of the input bus bar 30 to the other plate surface. Similarly to the input bus bar 30, the output bus bar 40 is a rectangular thick plate formed of a conductive material (copper or copper alloy in this embodiment), and includes a bolt insertion hole 41.

  The input bus bar 30 and the output bus bar 40 are disposed on the surface of the control circuit board 20 opposite to the surface on which the control circuit 22B is formed. The input bus bar 30 and the output bus bar 40 are arranged so that the end faces 32A and 42A facing each other are parallel to each other at an interval. That is, between the input bus bar 30 and the output bus bar 40, the end surface 32A of the input bus bar 30, the end surface 42A of the output bus bar 40, and the surface opposite to the side where the control circuit 22B is disposed on the insulating plate 21. The groove | channel 26 defined by these exists.

  The input bus bar 30 and the output bus bar 40 partially overlap the control circuit board 20, and the area where the bolt insertion holes 31 and 41 are arranged is out of the control circuit board 20. A part of the input bus bar 30 is exposed inside each first mounting window 24A. A part of the output bus bar 40 is exposed inside each second mounting window 24B.

  The separator 50 is disposed on the same surface of the control circuit board 20 as the surface on which the input bus bar 30 and the output bus bar 40 are disposed. The separating plate 50 includes a separating portion 51 disposed inside the groove 26 and two frame portions 52 respectively disposed at both ends of the separating portion 51. The isolation part 51 is an elongated rectangular plate and is disposed between the input bus bar 30 and the output bus bar 40. The two frame portions 52 are portions extending perpendicularly to the separator plate 50 from both ends of the separator plate 50, and are disposed with the input bus bar 30 and the output bus bar 40 interposed therebetween.

A method of forming the circuit structure 11 configured as described above is, for example, as follows (see FIG. 9).
First, the bus bars 30 and 40, the separator plate 50, and the insulating plate 21 are overlapped with the prepreg 54 that is the base material of the adhesive layer 53 interposed therebetween. Next, the bus bars 30 and 40, the separator 50, the insulating plate 21, and the laminate of the prepreg 54 are hot pressed to cure the prepreg 54 and bond the bus bars 30 and 40, the separator 50 and the insulating plate 21. The resin constituting the prepreg 54 flows by hot pressing, and a part of the resin enters the gap between the separator 50 and the input bus bar 30 and the gap between the separator 50 and the output bus bar 40 and is cured. Thereafter, the insulating plate 21 may be machined with a drill to form the mounting windows 24 </ b> A and 24 </ b> B, and the conductor circuit 22 may be formed on the surface of the insulating plate 21.

  The semiconductor switching elements 60A and 60B are power MOSFETs, and include a housing 61 and a drain terminal 62, a source terminal 63, and a gate terminal 64 provided in the housing 61. The drain terminal 62 is disposed on the lower surface of the housing 61. Further, the source terminal 63 and the gate terminal 64 protrude from the side surface of the housing 61.

  Of the six semiconductor switching elements 60A and 60B, three semiconductor switching elements (first semiconductor switching element 60A) constitute a set of first element group 65A. Of the six semiconductor switching elements 60A and 60B, the remaining three semiconductor switching elements (second semiconductor switching elements 60B) constitute a set of second element group 65B.

  As shown in FIG. 4, each first semiconductor switching element 60A is disposed inside the first mounting window 24A. The drain terminal 62 is connected to a part of the input bus bar 30 exposed inside the first mounting window 24A, the source terminal 63 is connected to the connection circuit 22A on the control circuit board 20, and the gate terminal 64 is connected to the control circuit 22B. Are connected to each other. Similarly, the second semiconductor switching element 60B is disposed inside the second mounting window 24B. The drain terminal 62 is connected to a part of the output bus bar 40 exposed inside the second mounting window 24B, the source terminal 63 is connected to the connection circuit 22A on the control circuit board 20, and the gate terminal 64 is connected to the control circuit 22B. Are connected to each other. The connection can be made with solder H, for example.

  By arranging in this way, three semiconductor switching elements 60A and 60B connected in parallel form one set, and two sets of semiconductor switching elements 60A and 60B are connected in series. The two sets of semiconductor switching elements 60A and 60B are arranged back to back.

  The reason why the plurality of semiconductor switching elements 60A and 60B are set as one set is to cope with a large current. That is, by connecting a plurality of semiconductor switching elements 60A and 60B in parallel, the total amount of current that can be passed through the power supply circuit can be increased.

  The two sets of semiconductor switching elements 60A and 60B are arranged back to back for the following reason.

  In general, in a switch using a MOSFET, a parasitic diode due to a pn junction is generated between a source and a drain. Therefore, even if the gate is turned off, a current flows through the parasitic diode from the source side to the drain side, so that the signal from the source side to the drain side cannot be turned off. For this reason, when the voltage of the auxiliary battery 91 becomes higher than that of the main battery 90 (when idling is stopped, for example), the current flows from the auxiliary battery 91 through the parasitic diode even though the switch is off. It may flow into the battery 90. By connecting two sets of MOSFETs in series so that the directions of the parasitic diodes are opposite to each other, bidirectional current can be cut off.

  The input bus bar 30 has a fastening terminal 71A connected to a harness 70A connected to the main battery 90, a power terminal 72A (stud bolt) inserted through the bolt insertion hole 31, and a nut tightened at the tip of the power terminal 72A. 73A. In addition, a fastening terminal 71B connected to a harness 70B connected to the auxiliary battery 91 is fastened to the output bus bar 40 at a power terminal 72B (stud bolt) inserted into the bolt insertion hole 41 and the tip of the power terminal 72B. It is fixed with a nut 73B.

  The casing 80 includes a case 81 and a cover plate 82. The case 81 is a tray-like case having an outer shape that is slightly larger than the outer shape of the switching substrate 10. The case 81 covers the entire surface of the switching substrate 10 on which the control circuit board 20 is disposed. The cover plate 82 is a rectangular plate having an outer shape equal to the outer shape of the control circuit board 20. The cover plate 82 is overlaid on the switching substrate 10 on the back side of the region where the control circuit board 20 is disposed. Both the case 81 and the cover plate 82 are made of synthetic resin.

(Effect of this embodiment)
According to the present embodiment, the bus bars 30, 40, the control circuit board 20, and the semiconductor switching elements 60A, 60B necessary for the switching board 10 arranged between the main battery 90 and the auxiliary battery 91 are simply laid out. The switching substrate 10 having a simple configuration can be provided.

<Modification>
A modification of the present invention will be described with reference to FIG. In the switching substrate 101 of this modification, the input bus bar 110 has a first convex portion 111A and a first concave portion 111B, and the output bus bar 120 has a second convex portion 121A and a second concave portion 121B. Except for this, the configuration is the same as in the embodiment. In the switching substrate 101, the same components as those of the embodiment are denoted by the same reference numerals and description thereof is omitted.

  The input bus bar 110 has a plurality of first convex portions 111 </ b> A that protrude toward the output bus bar 120 at the end edge 111 on the output bus bar 120 side. The plurality of first convex portions 111A are provided at a constant pitch. A region between two adjacent first protrusions 111 </ b> A and 111 </ b> A is a first recess 111 </ b> B that is recessed on the opposite side to the output bus bar 120.

  The output bus bar 120 has a plurality of second convex portions 121 </ b> A that protrude toward the input bus bar 110 at the edge 121 on the input bus bar 110 side. The plurality of second convex portions 121A are provided at a constant pitch. A region between two adjacent second convex portions 121 </ b> A and 121 </ b> A is a second concave portion 121 </ b> B that is recessed on the opposite side to the input bus bar 110.

  The plurality of first protrusions 111A and the plurality of second protrusions 121A are alternately arranged. Each of the plurality of first convex portions 111A is disposed to face the second concave portion 121B, and the protruding end is located in the second concave portion 121B. Each of the plurality of second convex portions 121A is disposed to face the first concave portion 111B, and the protruding end is located in the first concave portion 111B.

  According to the above configuration, it is possible to avoid the control circuit board 20 from being broken along the gap between the input bus bar 110 and the output bus bar 120 when an unexpectedly large force is applied to the switching board 101.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.
(1) In the above embodiment, the example in which the isolation part 51 of the separator 50 is arranged inside the groove 26 is shown. However, for example, after the control circuit board 20 and the bus bars 30 and 40 are bonded, The groove 26 may be filled by pouring and curing a thermosetting resin.

(2) In the above embodiment, the auxiliary power source is the auxiliary battery 91. However, as the auxiliary power source, for example, a power storage device such as a secondary battery or an electric double layer capacitor can be used.

(3) In the above embodiment, the mounting windows 24A and 24B and the semiconductor switching elements 60A and 60B are one set, but the number of semiconductor switching elements constituting one set is two or four or more. It doesn't matter. Similarly, the number of mounting windows constituting one set may be two or four or more.

DESCRIPTION OF SYMBOLS 10, 101 ... Switching board 11 ... Circuit structure 20 ... Control circuit board 21 ... Insulating board 22 ... Conductor circuit 22A ... Control circuit 22B ... Connection circuit 24A ... 1st mounting window 24B ... 2nd mounting window 30, 110 ... Input bus bar 40, 120 ... output bus bar 60A ... first semiconductor switching element 60B ... second semiconductor switching element 62 ... drain terminal 63 ... source terminal 64 ... gate terminal 90 ... main battery (main power supply)
91 ... Sub battery (auxiliary power supply)
111 ... End edge 111A ... First convex portion 111B ... First concave portion 121 ... End edge 121A ... Second convex portion 121B ... Second concave portion

Claims (2)

In a vehicle including a main power source and an auxiliary power source, a switching board disposed between the main power source and the auxiliary power source,
An insulating plate made of an insulating material, a conductor circuit disposed on one surface of the insulating plate, and a plurality of mounting windows penetrating from the surface of the insulating plate on which the conductor circuit is provided to the opposite surface. A circuit structure comprising: a control circuit board; and an input bus bar and an output bus bar arranged on the opposite surface of the insulating plate at an interval from each other;
A plurality of semiconductor switching elements mounted on the circuit structure and having a drain terminal, a source terminal and a gate terminal;
The conductor circuit includes a control circuit, and a connection circuit disposed between the input bus bar and the output bus bar,
A part of the plurality of mounting windows is a first mounting window in which a part of the input bus bar is exposed on the inside, and the other mounting window is a first window in which a part of the output bus bar is exposed on the inside. 2 mounting windows,
Some of the plurality of semiconductor switching elements are disposed inside the first mounting window, the drain terminal is connected to a part of the input bus bar, and the source terminal is connected to the connection circuit. The gate terminal is a first semiconductor switching element connected to the control circuit, the other semiconductor switching element is disposed inside the second mounting window, and the drain terminal is a part of the output bus bar. A switching substrate, being a second semiconductor switching element connected, the source terminal connected to the connection circuit, and the gate terminal connected to the control circuit. The input bus bar is disposed at an edge on the output bus bar side between a plurality of first convex portions projecting toward the output bus bar and two adjacent first convex portions, and the output bus bar is A first recess recessed on the opposite side,
The output bus bar is disposed at an edge on the input bus bar side, between a plurality of second convex portions projecting toward the input bus bar, and the two adjacent second convex portions. The switching substrate according to claim 1, further comprising a second recess recessed on the opposite side.

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